drm/hisilicon/hibmc: Fix preferred depth and bpp

Set the preferred color depth to 24 bits and the fbdev bpp to 32
bits. This will signal XRGB8888 as default format to clients.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20221123115348.2521-2-tzimmermann@suse.de

drivers/gpu/drm/hisilicon/hibmc/hibmc_drm_drv.c

@@ -106,7 +106,7 @@ static int hibmc_kms_init(struct hibmc_drm_private *priv)
 	dev->mode_config.max_width = 1920;
 	dev->mode_config.max_height = 1200;
 
-	dev->mode_config.preferred_depth = 32;
+	dev->mode_config.preferred_depth = 24;
 	dev->mode_config.prefer_shadow = 1;
 
 	dev->mode_config.funcs = (void *)&hibmc_mode_funcs;
@@ -340,7 +340,7 @@ static int hibmc_pci_probe(struct pci_dev *pdev,
 		goto err_unload;
 	}
 
-	drm_fbdev_generic_setup(dev, dev->mode_config.preferred_depth);
+	drm_fbdev_generic_setup(dev, 32);
 
 	return 0;